Shaving device



July 13, 1943; G. DALKQwlTz 2,324,070

SHAVING DEVICE Filed June 22, 1957 2 sheets-sheet 1 m II Ff-5.7 I

58 a vzfnnbnnmm.

INVENTOR God myalomlj July 13, I1943.

G. DALKown-z l A SHAVING DEVICE Filed June 22, 1937 2 'Sheets-Sheet 2'Patented July 13, 1943 Sl-IAVING DEVICE Godfrey Dalkowitz, Brooklyn, N.Y.; assignor to American Safety Razor Corporation, Brooklyn, N. Y., acorporation of Virginia Application June zz, 1931, serial No. l149,570

(c1. en -43) 3 Claims. This invention relates to dry shavers of the typein which the shaving operai-,ion is effected` l by the interaction ofrelatively movable cutting edges and without the use of detergentstoprepare the hair.

Among the objects of my invention are the provision in a shaving deviceof a pair of cutting edges and means for moving said cutting edgesdiagonally toward each other; the provision in a shaving device ofv apair of cutting edges and means for imparting relative movement to saidcutting edges said movement having a component moving them directlytoward each other and another component ,at right angles thereto movingthem laterally of each other; the provision in a shaving device ofopposed parallel cutting edges and means for moving said edgesdiagonally toward each other; the provision in a dry shaving device ofopposed parallel cutting edges and means for imparting relative movementto said edges, said movement having a component perpendicular to saidedges and a lateral component at right angles thereto; the provision ina dry shaving device of opposed parallel cutting edges and means forimparting relative movement to said edges, said movement having acomponent perpendicular to said edges and a lateral component at rightangles thereto and said lateral component exceeding the perpendicularcomponent; the provision in a shaving device of relatively7 movablecoaxial spiral cutting edges; the provision in a shaving device ofrelatively movable coaxial spiral cutting edges and means for movingsaid edges into positions in which they are always parallel to eachother; I

the provision in a shaving device of relatively rotatable coaxialspira-l cutting edges; the provision in a shaving device of relativelymovable coaxial spiral cutting edges formed on spirals identical indiameter and pitch; the provision in a shaving device of relativelyrota-*able coaxial spiral cutting edges formed on spirals identical indiameter and pitch; the provision in a shavdevice of relativelyoscillatable coaxial spiral cutting edges; the provision in a shavingdevice. ci a shear plate of cylindrical configuration and a relativelymovable cutter of similar cylindrical configuration and spira-llycontoured cutting edges on the shear plate ind on the cutter; theprovision in a shaving device of a shear plate of cylindricalconfiguration and a relatively rotaiable cutter of similar cylindricalconfiguration and spirally contoured cutting edges on the shear plateand on said cutter; the provision in a shaving device of a shear plateof cylindrical conguration and a relatively oscillatable cutter ofsimilar cylindrical configuration and spirali! contoured cutting edgeson the shear plate and von the cutter; the provision of a shear plate ofcylindrical configuration having slots therein the end portions of whichare wider than the middle portions, cutting edges formed on the sidewalls of the middle portions of said slots, and a cutter adapted to'cooperate with said cutting edges on the Vshea-r plate to effect acutting action; and the provision of a shear plate of cylindricalconfiguration having slots therein and the walls of said slots beingprovided with cutting edges and guard means associated with said shearplate having slots adapted to register with the slots of said shearplate and having widened portions adapted to receive hair and means toguide it toward the cutting edges of the slots of the shear p ate.

For the attainment of these objects and such other objects as willhereinafter appear or be pointed out I have illustrated severalembodiments oi my invention in the drawings in which:

Figure l is a longitudinal sectional view through one embodiment of myinvention taken substantially on the line I-I of Figure 3, looking inthe direction of the arrows;

Figure 2 is an end view thereof;

Figure 3 is a plan view thereof;

Figure 4 is a sectional view taken substantially on theline 4 4 ofFigure 1, looking in lthe direction of the arrows;

Figure 5 is an enlarged view of a detail of the embodiment of Figure 1;

Figures 6 and 7 are sectional views taken respectively on the lines 6-6and 1-1 oi' Figure 5 v looking in the direction of the arrows:

Figure 8 is a sectional view of a portion of a modified form of theembodiment of Figure 1.

taken substantially on the line 8-8 oi' Figure 9 looking in thedirection of the arrows;

Figure 9 is a plan view of a portion of the modiiled form of Figure 8;

Figures 10 and 11 illustrate further modifications, these views beingsimilar to Figure 8;

Figure l2 is a transverse sectional view of another embodiment of myinvention, this view being taken substantially on the line ifii2 of FIE-ure 13; and

Figure 13 is a longitudinal sectional view of the embodiment of Figurel2 taken on the line I3-I3 of Figure 12, and looking in the direction ofAthe arrows.

Beforeproceeding with the detailed 'description of the variousembodiments of my invention- `wide.

will premise that in all of them'the cutting is eected by cutting edgesrelatively movable atoward each other and laterally of each other so asto eiect a "slicing cut. In all of illustrated embodiments these cuttingedges are at all times parallel to each other so that the area ofcutting is a distributed one instead of taking place successively atvarious points as in the ordinary scissors, and in all of them thecutting edges are spirally contoured and the relative movement is arotational movement about axis of the spirals and without any axialmovement.

On referring particularly to Figures 1 to 4 in clusive it will beobserved that I there show a shaving device comprising a cylindricalcutter 2@ surrounded by a casing 22'and rotatably mounted therein. 'I'hecutter 20 is shown as provided with a pair oi.' spiral threads 24running around it and one edge portion 26 of each of these threads isformed into a continuous helica or spiral cutting edge that is adapted,conjointly with a plurality of cutting edges 28 formed on the side wallsof ribs 34 separated by-slots 30 provided in the upper wall of thecasing and forming what may be termed a shear plate, to effect a cuttingaction. While I have shown two such spiral cutting edges 28, it is to beunderstoodthat more than this number or only one such spiral cuttingedge may be used, the exact number not being essential.

The cutting edges 28 o1' the ribs lie in the cylindrical surface formingthe walls oi' the bore 32 within which the cutter is positioned, and thecutting edges 28 also are helically or spirally pitched. While they maybe part of one helix this is not necessarily so. In the drawings I haveshown the cutting edges 28 as being parts of a plurality of helices, theexact number oi' helices indicated being four. However the exact numberused is not essential to my invention and may be greater or less thanfour.

The pitch of the helices along which the cutting edges oi the shearplate and of the cutter are formed are however identical, whereby theyare always parallel to each other.

When the cutter 2D is rotated it will be obvious that the cutting edge26 approaches the cutting edges 28 in a diagonal direction while alwaysre malning parallel to said cutting edges in all positions thereof. Asit crosses a cutting edge 28 there will be simultaneous engagement ofall portions of the cutting edge 28 with a section of the cutting edge26.

By referring to Figures 5, 6 and 7 which illustrate the shearplate on alarger scale it will be observed that the ribs 34 are shown as havingtheir side walls at their mid-portions parallel, and the same isptrue ofthe slots. It will also be observed by referring to Figure 6 that theribs at this point are shown as relatively thin so that the cuttingedges 26 and 28 are located relatively near the surface to be shaved,and a close shave may therefore be effected. It will further be observedthat the slots are shown as relatively narrow at this point, while theribs are relatively At their end portions however the slots are shown at36 as relatively wide, while the ribs are relatively narrow as shown at38. Intermediate their mid portions and their end portions, the slotsare shown as gradually changing in width so as to merge respectivelyinto the end portions and into the middle portions, and the same is trueof the ribs. slot width of the order of between twelve one1 thousandthsand twenty one-thousandths of an inch at the narrow portions of theslots and a corresponding rib thickness of four one-thousandths of aninch give very satisfactory results. It will also be observed fromFigure 7 that the ribs are shown as thicker near their end portion. Thisis for the purpose of strengthening the ribs and to compensate for thereduction in their width andis unobjectionable because at this point noshaving takes piace and it is unnecessary for the ribs to be thin. A

Consideration of what takes place during the shaving operation willindicate the desirability of this construction. The shaver when in useil intended to be moved transversely to its longitudinal extent that isto say, substantially in the direction of the slots and the wideentrance I have found in practice that a portion of the slots will serveto catch a great proportion of the hairs encountered by the shaver, andas the shaver is moved further these hairs will be guided into thenarrow cutting pon tions of the slots. If the entrance portions weremade narrow a much smaller proportion of the hairs would enter theslots. Such hairs as do not enter the slots would pass under the ribsand escape the shaving action,

The cutter is shown as provided with Journalled portions 40 and againstthese journalled portions press plungers 42 actuated by helical springs44 .both plungers and springs being posiytioned within bores 46 providedin the casing 22 these bores being closed by set screws 48. As a resultof the resilient pressure of the plungers 42 the cutter is at all timeskept in contact with the shear plate portion of the casing, so that theproper cutting action will be obtained.

Suitable means for rotating the cutter are shown by way of example inthe form of a train of gears comprising a gear 50 fastened directly tothe cutter, a gear 52 in mesh therewith, and the intermeshing gears 54and 5G, the latter positioned on the drive shaft 58, while the gears 52and 54 are on an arbor 88 iournalled in the casing 22.

The bore 32 of the casing is shown as closed by end pieces 52 held inplace in any suitable or preferred manner and vent openings 64 are shownas positioned in the sides of the casing for the purpose of permittingthe shaving waste to escape.

At the ends of the shear plate portion the casing 22 may be thickened asindicated at 88 thereby serving to reinforce said shearv plate portion,which, as has already been mentioned, should be made relatively thin toeffect close shaving. l

In Figures 8 and 9 I have shown a modificaof the embodiment of Figure 1in which guard members l0 and 'l2 are shown superposed over the shearplates. Each guard member is shown as provided with ribs -14 positionedso as to register with the ribs 34' of the shear plate, and these ribsare shown as having tapered end portions, as indicated at 16, wherebythe slots between the ribs flare outwardly. The outer surfaces of theribs 'I4 of both members 10 and 'I2 are shown lying in a single plane,so that they present a substantially at surface intended to be placed incontact with the surface to be shaved when the shaver is in use. It willbe noted that the slots between the ribs are shown as oi maximum depthat their outer portions and decrease in depth inwardly to a point atwhich a portion 18 of the ribsofthe shear plate is exposed. Itis at thislatter portion that the close shaving is effected, although the cuttingaction is not confined thereto While the ribs 14 have been shown as ofuniform width in a vertical direction, that is, passing from their outersurfaces downward, it may be found desirable for certain purposes tovary the width so that it is least at their outer surfaces, whereby theslots between the ribs will be widest at their outer portions andnarrowest where they meet the ribs of the casing.

It would be superiiuous to describe the other details, such as thecutter and the casing-22,

since these are intended to be lsimilar to the correspondingly numberedparts of the embodiment of Figure i. It may be mentioned however uhatcoiled compression spring |3| is shown as positioned on each pin |30,and as abutting against the trunnion |22 at one end and against thewhile I have indicated the guard members 10 and '|2 as removablyfastened to the shear plate by screws 80 and 82 it is understood thatthey may be formed as integral portions of the casing 22' or that theymay be permanently rather than removably secured thereto.

A modification in which the shear plate 94 is shown as projecting beyondthe upper surfaces or the guard members 90 and 92, whichare otherwisesimilar to the guard members '10 and 12 of Figures 8 and 9, is shown inFigure 10.

A construction in some respects the reverse that of Figure 10 is shownin Figure 11. In this case the projecting portions |04 of the shearplate are situated at the lowest point of a concavity formed by thepeculiarly shaped guard members |80 and |02, which have the sideportions of their outer surfaces raised above their inner portions.

In Figures l2 and 13 I have shown a construction in which while thecutting edges both of the shear plate and of the cutter are formed onsimilar coaxial spirals, their relative motion is an oscillatory oneinstead of a rotating one. This enables a double cutting action to takeplace and for this purpose both side wallsof the ribs cutter plate atits other end, so as to press the cutter plate |34 against the shearplate.

The shear plate proper is constituted by ribs |37 having slots |38between each pair of ribs andthe cutter is similarly constituted by ribs|40 having slots |42 intermediate each pair of ribs. The cutting edgesare formed on both side walls of the ribs and as the cutter isoscillated the respective cutting edges of the cutter and the shearplate effect a cutting action as in the other embodiments heretoforedescribed, except that in said other embodiments the cutter moves in onedirection, while in the present instance the cutter moves backwards andforwards and is active in both directions. It will be understood thatother features mentioned in the preceding embodiments and not inconnection with this embodiment may also be incorporated therein.

While I have shown and described several illustrative embodiments of myinvention it will b e understood that the saine may beembodied in manyother forms as will be obvious to those skilled in the art, and that thedisclosure herein is intended to be by way of illustration only and isnot to be interpreted in a limiting sense, and that Ido not limit myselfother than as called for bythe prior art.

Having thus described my invention and illustrated its use, what I claimas new and desire to secure by Letters Patent is:

i'. A shaving device having a rotatable cutting member with a pair ofsimilar coaxial spiral cutting edges thereon, and complementarystationary cutting edges that are segments of four member are formed,and means for rotating said f cutting member relatively to saidstationary cutin the shear plate as well as both sides of the ribs ofthe cutter are provided with cutting edges. Since the oscillationtakesplace 'through a limited arc and not through a complete circumferencethe cutter need not be made in the form of a cylinder, but may compriseonly a portion of a cylindrical surface.

In the illustrative embodiment of Figures l2 and 13 I have shown a yoke|251 mounted for oscillation about trunnions |22 journalled in thecasing |36 and actuated by a crank |24 carried bv a rotating drive shaft|26 slidable in the slot i 28 provided on the yoke. A pin |30 is shownting edges.

l2. A shaving device having arotatable cutting member provided withcutting edges thereon in the form of double screw threads andcomplementary stationary cutting edges that are segments of quadruplescrew threads coaxial with and having the same pitch and diameter assaid screw threads on said cutting member, and means for rotating saidcutting member.

3. A shaving device having a rotatable cutting member provided withcutting edges thereon in the form of double screw threads andcomplementary stationary cutting edges that are segments of quadruplescrew threads coaxial with and having the same pitch and diameter assaid screw threads on said cutting member, means for rotating saidcutting member, and resilient means for pressing saidrotatable memberagainst

